1. Field of the Invention
The present invention is directed to laminated building panels with protection from insects, molds, and fungi. More particularly, the present invention is directed to building panels comprising a sandwich of two skins bonded to a core of a firm solid insulating material, or the insulating material itself, that is protected against attack by many types of insects, molds, and fungi.
2. Description of the Related Art
Pests such as termites, carpenter ants, insects, and so forth have long been a scourge of wooden buildings. Extensive efforts to control insect infestation of buildings have been undertaken. Many chemical preparations for exterior application to a building or foundation have been developed. Many of these chemicals are also hazardous to pets and humans and have consequently been banned.
For example, creosote has long been used to preserve wood and is now unavailable for residential use because creosote is carcinogenic.
Copper-chrome-arsenate (CCA) solutions have long been used to treat wood under high pressure and comprise the majority of treated wood now available. CCA treated wood is, however, highly insecticidal and fungicidal and must be handled with considerable extraordinary care.
One such effort to develop a preservative to deter insect and vermin infestation is found in U.S. Pat. No. 2,186,134, issued to Chapman on Jan. 9, 1940. Chapman discloses the use of a preservative composition comprising a halogenated phenol and an alkali metal salt of boric acid in an aqueous solution which is applied to fiber based building materials such as fiberboard, insulation made of paper and so forth. Engineered materials unknown to Chapman now comprise an important portion of the available range of building materials. One such example is the prefabricated insulated building panels comprising a core of expanded polystyrene (EPS), which may be about 31/2-111/2 inches (8.9-40 cm) thick, sandwiched between two wood-based sheets or other skins, such as metal. The panels may be in any convenient size, with the most popular size being about 4 feet by 8 feet (1.2 m.times.2.4 m). The wood-based panels, may be tempered hardboard, chipboard, particleboard, oriented strand board, and the like. The two skins are each typically at least 3/8 inch (0.95 cm) thick when the panels are intended to form load bearing walls. The panels are adhesively bonded by a urethane laminating adhesive. Such prefabricated building panels have become extremely popular because they provide high insulation value, and virtually eliminate drafts through the roofs, walls and floors. They provide economical alternatives to stick-built structures in part by reducing the framing time of the construction of a new home or other buildings by about two-thirds.
It has been found, however, that in some situations such panels may be attacked by insects, molds, or fungus. Insects may bore through the oriented strand board or waferboard into the expanded polystyrene core (EPS), where they may nest. The environment within the core of the building panel provides good living conditions for most insects since it is usually warm during the winter, cool during summer and non-toxic. Conventional chemical treatments may be applied to prevent such attacks in the same fashion as they are applied to other wood-based structures. Regular application of such chemicals, however, is expensive and inconvenient. In addition, such chemicals may well be significantly toxic to humans and pets.
Accordingly, there is a need for an energy efficient laminated building panel that resists attack by insects, mold and fungus.